1 #ifndef _ASM_POWERPC_PAGE_H 2 #define _ASM_POWERPC_PAGE_H 3 4 /* 5 * Copyright (C) 2001,2005 IBM Corporation. 6 * 7 * This program is free software; you can redistribute it and/or 8 * modify it under the terms of the GNU General Public License 9 * as published by the Free Software Foundation; either version 10 * 2 of the License, or (at your option) any later version. 11 */ 12 13 #ifndef __ASSEMBLY__ 14 #include <linux/types.h> 15 #else 16 #include <asm/types.h> 17 #endif 18 #include <asm/asm-compat.h> 19 #include <asm/kdump.h> 20 21 /* 22 * On regular PPC32 page size is 4K (but we support 4K/16K/64K/256K pages 23 * on PPC44x). For PPC64 we support either 4K or 64K software 24 * page size. When using 64K pages however, whether we are really supporting 25 * 64K pages in HW or not is irrelevant to those definitions. 26 */ 27 #if defined(CONFIG_PPC_256K_PAGES) 28 #define PAGE_SHIFT 18 29 #elif defined(CONFIG_PPC_64K_PAGES) 30 #define PAGE_SHIFT 16 31 #elif defined(CONFIG_PPC_16K_PAGES) 32 #define PAGE_SHIFT 14 33 #else 34 #define PAGE_SHIFT 12 35 #endif 36 37 #define PAGE_SIZE (ASM_CONST(1) << PAGE_SHIFT) 38 39 /* We do define AT_SYSINFO_EHDR but don't use the gate mechanism */ 40 #define __HAVE_ARCH_GATE_AREA 1 41 42 /* 43 * Subtle: (1 << PAGE_SHIFT) is an int, not an unsigned long. So if we 44 * assign PAGE_MASK to a larger type it gets extended the way we want 45 * (i.e. with 1s in the high bits) 46 */ 47 #define PAGE_MASK (~((1 << PAGE_SHIFT) - 1)) 48 49 /* 50 * KERNELBASE is the virtual address of the start of the kernel, it's often 51 * the same as PAGE_OFFSET, but _might not be_. 52 * 53 * The kdump dump kernel is one example where KERNELBASE != PAGE_OFFSET. 54 * 55 * PAGE_OFFSET is the virtual address of the start of lowmem. 56 * 57 * PHYSICAL_START is the physical address of the start of the kernel. 58 * 59 * MEMORY_START is the physical address of the start of lowmem. 60 * 61 * KERNELBASE, PAGE_OFFSET, and PHYSICAL_START are all configurable on 62 * ppc32 and based on how they are set we determine MEMORY_START. 63 * 64 * For the linear mapping the following equation should be true: 65 * KERNELBASE - PAGE_OFFSET = PHYSICAL_START - MEMORY_START 66 * 67 * Also, KERNELBASE >= PAGE_OFFSET and PHYSICAL_START >= MEMORY_START 68 * 69 * There are two was to determine a physical address from a virtual one: 70 * va = pa + PAGE_OFFSET - MEMORY_START 71 * va = pa + KERNELBASE - PHYSICAL_START 72 * 73 * If you want to know something's offset from the start of the kernel you 74 * should subtract KERNELBASE. 75 * 76 * If you want to test if something's a kernel address, use is_kernel_addr(). 77 */ 78 79 #define KERNELBASE ASM_CONST(CONFIG_KERNEL_START) 80 #define PAGE_OFFSET ASM_CONST(CONFIG_PAGE_OFFSET) 81 #define LOAD_OFFSET ASM_CONST((CONFIG_KERNEL_START-CONFIG_PHYSICAL_START)) 82 83 #if defined(CONFIG_RELOCATABLE) 84 #ifndef __ASSEMBLY__ 85 86 extern phys_addr_t memstart_addr; 87 extern phys_addr_t kernstart_addr; 88 #endif 89 #define PHYSICAL_START kernstart_addr 90 #else 91 #define PHYSICAL_START ASM_CONST(CONFIG_PHYSICAL_START) 92 #endif 93 94 #ifdef CONFIG_PPC64 95 #define MEMORY_START 0UL 96 #elif defined(CONFIG_RELOCATABLE) 97 #define MEMORY_START memstart_addr 98 #else 99 #define MEMORY_START (PHYSICAL_START + PAGE_OFFSET - KERNELBASE) 100 #endif 101 102 #ifdef CONFIG_FLATMEM 103 #define ARCH_PFN_OFFSET (MEMORY_START >> PAGE_SHIFT) 104 #define pfn_valid(pfn) ((pfn) >= ARCH_PFN_OFFSET && (pfn) < (ARCH_PFN_OFFSET + max_mapnr)) 105 #endif 106 107 #define virt_to_page(kaddr) pfn_to_page(__pa(kaddr) >> PAGE_SHIFT) 108 #define pfn_to_kaddr(pfn) __va((pfn) << PAGE_SHIFT) 109 #define virt_addr_valid(kaddr) pfn_valid(__pa(kaddr) >> PAGE_SHIFT) 110 111 #define __va(x) ((void *)((unsigned long)(x) + PAGE_OFFSET - MEMORY_START)) 112 #define __pa(x) ((unsigned long)(x) - PAGE_OFFSET + MEMORY_START) 113 114 /* 115 * Unfortunately the PLT is in the BSS in the PPC32 ELF ABI, 116 * and needs to be executable. This means the whole heap ends 117 * up being executable. 118 */ 119 #define VM_DATA_DEFAULT_FLAGS32 (VM_READ | VM_WRITE | VM_EXEC | \ 120 VM_MAYREAD | VM_MAYWRITE | VM_MAYEXEC) 121 122 #define VM_DATA_DEFAULT_FLAGS64 (VM_READ | VM_WRITE | \ 123 VM_MAYREAD | VM_MAYWRITE | VM_MAYEXEC) 124 125 #ifdef __powerpc64__ 126 #include <asm/page_64.h> 127 #else 128 #include <asm/page_32.h> 129 #endif 130 131 /* align addr on a size boundary - adjust address up/down if needed */ 132 #define _ALIGN_UP(addr,size) (((addr)+((size)-1))&(~((size)-1))) 133 #define _ALIGN_DOWN(addr,size) ((addr)&(~((size)-1))) 134 135 /* align addr on a size boundary - adjust address up if needed */ 136 #define _ALIGN(addr,size) _ALIGN_UP(addr,size) 137 138 /* 139 * Don't compare things with KERNELBASE or PAGE_OFFSET to test for 140 * "kernelness", use is_kernel_addr() - it should do what you want. 141 */ 142 #define is_kernel_addr(x) ((x) >= PAGE_OFFSET) 143 144 #ifndef __ASSEMBLY__ 145 146 #undef STRICT_MM_TYPECHECKS 147 148 #ifdef STRICT_MM_TYPECHECKS 149 /* These are used to make use of C type-checking. */ 150 151 /* PTE level */ 152 typedef struct { pte_basic_t pte; } pte_t; 153 #define pte_val(x) ((x).pte) 154 #define __pte(x) ((pte_t) { (x) }) 155 156 /* 64k pages additionally define a bigger "real PTE" type that gathers 157 * the "second half" part of the PTE for pseudo 64k pages 158 */ 159 #if defined(CONFIG_PPC_64K_PAGES) && defined(CONFIG_PPC_STD_MMU_64) 160 typedef struct { pte_t pte; unsigned long hidx; } real_pte_t; 161 #else 162 typedef struct { pte_t pte; } real_pte_t; 163 #endif 164 165 /* PMD level */ 166 #ifdef CONFIG_PPC64 167 typedef struct { unsigned long pmd; } pmd_t; 168 #define pmd_val(x) ((x).pmd) 169 #define __pmd(x) ((pmd_t) { (x) }) 170 171 /* PUD level exusts only on 4k pages */ 172 #ifndef CONFIG_PPC_64K_PAGES 173 typedef struct { unsigned long pud; } pud_t; 174 #define pud_val(x) ((x).pud) 175 #define __pud(x) ((pud_t) { (x) }) 176 #endif /* !CONFIG_PPC_64K_PAGES */ 177 #endif /* CONFIG_PPC64 */ 178 179 /* PGD level */ 180 typedef struct { unsigned long pgd; } pgd_t; 181 #define pgd_val(x) ((x).pgd) 182 #define __pgd(x) ((pgd_t) { (x) }) 183 184 /* Page protection bits */ 185 typedef struct { unsigned long pgprot; } pgprot_t; 186 #define pgprot_val(x) ((x).pgprot) 187 #define __pgprot(x) ((pgprot_t) { (x) }) 188 189 #else 190 191 /* 192 * .. while these make it easier on the compiler 193 */ 194 195 typedef pte_basic_t pte_t; 196 #define pte_val(x) (x) 197 #define __pte(x) (x) 198 199 #if defined(CONFIG_PPC_64K_PAGES) && defined(CONFIG_PPC_STD_MMU_64) 200 typedef struct { pte_t pte; unsigned long hidx; } real_pte_t; 201 #else 202 typedef pte_t real_pte_t; 203 #endif 204 205 206 #ifdef CONFIG_PPC64 207 typedef unsigned long pmd_t; 208 #define pmd_val(x) (x) 209 #define __pmd(x) (x) 210 211 #ifndef CONFIG_PPC_64K_PAGES 212 typedef unsigned long pud_t; 213 #define pud_val(x) (x) 214 #define __pud(x) (x) 215 #endif /* !CONFIG_PPC_64K_PAGES */ 216 #endif /* CONFIG_PPC64 */ 217 218 typedef unsigned long pgd_t; 219 #define pgd_val(x) (x) 220 #define pgprot_val(x) (x) 221 222 typedef unsigned long pgprot_t; 223 #define __pgd(x) (x) 224 #define __pgprot(x) (x) 225 226 #endif 227 228 struct page; 229 extern void clear_user_page(void *page, unsigned long vaddr, struct page *pg); 230 extern void copy_user_page(void *to, void *from, unsigned long vaddr, 231 struct page *p); 232 extern int page_is_ram(unsigned long pfn); 233 234 struct vm_area_struct; 235 236 typedef struct page *pgtable_t; 237 238 #include <asm-generic/memory_model.h> 239 #endif /* __ASSEMBLY__ */ 240 241 #endif /* _ASM_POWERPC_PAGE_H */ 242